This invention relates, in general, to bicycles, and, more particularly, to a system for adjusting the vertical height of the handlebars. Heretofore, the method of vertically adjusting the handlebars of a bicycle has been a rather cumbersome and time consuming operation and one which has consistently required the operator to be in a dismounted state to bring about the necessary adjustment. Most generally, the methods for altering the height of the handlebars have involved the use of appropriate tools in order to bring about a loosening of cooperating threaded elements in order to free the support or stem for shifting into desired position and then a corresponding tightening operation.
In more recent years, efforts have been considered to effect this type of adjustability without requiring the operator to resort to tools which, on many critical occasions, are unavailable. It has been extremely desirable to provide a system which would permit adjusting the height of the handlebars but would not require the rider to dismount. An early effort is illustrated by British patent specification No. 9124, Apr. 1896; and a more recent effort is shown in Swiss Pat. No. 203007, June 1939. Another particular effort along these lines is set forth in the applicant's co-pending application, Ser. No. 1,443, filed Jan. 8, 1979 and now U.S. Pat. No. 4,260,171 in an invention entitled "Bicycle Gear Shift System." However, these prior efforts have not proved efficacious in practice. They inordinately are devoid of a desired simplicity of construction which would render same highly durable and reliable in operation as well as economical in production and it is apparent that such prior constructions did not possess that degree of positive lockability in the particular preselcted position to accord the operator a full sense of security.
Therefore, it is an object of the pesent invention to provide a system for adjusting the handlebars of a bicycle which comprehends a paucity of components which are durable and resistant to breakdown.
It is another object of the present invention to provide means for adjusting the height of the bicycle handlebars which is controlled by the simple to and fro shifting of a conveniently located control knob, the operation of which does not enhance the rider's peril in view of its facile movement and location.
A still further object of the invention is to provide a system for adjusting handlebars as stated which entails a positive interlock between movable and stationary components so that reliability is accorded and thereby relieving the rider of any concern as to the possibility of accidental travel of the handlebars from chosen position.
It is another object of the present invention to provide a system for adjusting bicycle handlebars which may be easily installed upon existing bicycles without requiring any costly or damaging modification thereof.
The present invention thus contemplates a handlebar-carrying stem which latter is vertically movable within the front fork tube of a bicycle and which stem internally pivotally mounts a lever carrying a latching pin for reception within a selected opening in a stationary element within the tube.